title: 5'-triphosphate-siRNA activates RIG-I-dependent type I interferon production and enhances inhibition of hepatitis B virus replication in HepG2.2.15 cells.
abstract: Hepatitis B virus (HBV) infection often results in acute or chronic viral hepatitis and other liver diseases including cirrhosis and hepatocellular carcinoma. Current therapies for HBV usually have severe side effects and can cause development of drug-resistant mutants. An alternative and safe immunotherapeutic approach for HBV infection is urgently needed for effective anti-HBV therapy. In this study, we propose a new strategy for anti-HBV therapy that activates type-I interferon (IFN) antiviral innate immunity through stimulating pattern-recognition receptors with RNA interference (RNAi) using a 5'-end triphosphate-modified small interfering RNA (3p-siRNA). We designed and generated a 3p-siRNA targeting overlapping region of S gene and P gene of the HBV genome at the 5'-end of pregenomic HBV RNA. Our results demonstrated that 3p-siRNA induced a RIG-I-dependent antiviral type-I IFN response when transfected into HepG2.2.15 cells that support HBV replication. The 3p-siRNA significantly inhibited HBsAg and HBeAg secretion from HepG2.2.15 cells in a RIG-I-dependent manner, and the antiviral effect of 3p-siRNA was superior to that of siRNA. Furthermore, 3p-siRNA had more pronounced inhibition effects on the replication of HBV DNA and the transcription of mRNA than that of siRNA. Finally, 3p-siRNA displayed antiviral activity with long-term suppression of HBV replication. In conclusion, our findings suggest that 3p-siRNA could act as a powerful bifunctional antiviral molecule with potential for developing a promising therapeutic against chronic HBV infection.
authors.affiliation: Division of Infection and Immunity, Department of Electromagnetic and Laser Biology, Beijing Institute of Radiation Medicine, 27 Taiping Rd, Beijing 100850, China.
authors.forename: Xiaojuan
authors.initials: X
authors.lastname: Chen
authors.forename: Yuanyu
authors.initials: Y
authors.lastname: Qian
authors.forename: Fei
authors.initials: F
authors.lastname: Yan
authors.forename: Jian
authors.initials: J
authors.lastname: Tu
authors.forename: Xingxing
authors.initials: X
authors.lastname: Yang
authors.forename: Yaling
authors.initials: Y
authors.lastname: Xing
authors.forename: Zhongbin
authors.initials: Z
authors.lastname: Chen
mesh_terms: D001483:Base Sequence; D000071457:DEAD Box Protein 58; D053487:DEAD-box RNA Helicases / Q000378:metabolism*; D004261:DNA Replication / Q000235:genetics; D056945:Hep G2 Cells; D006511:Hepatitis B Antigens / Q000235:genetics / Q000378:metabolism; D006515:Hepatitis B virus / Q000235:genetics* / Q000502:physiology*; D006801:Humans; D007113:Immunity, Innate; D007370:Interferon Type I / Q000096:biosynthesis* / Q000235:genetics; D011122:Polyphosphates / Q000737:chemistry*; D034622:RNA Interference; D012333:RNA, Messenger / Q000235:genetics; D034741:RNA, Small Interfering / Q000737:chemistry / Q000235:genetics*; D011971:Receptors, Immunologic; D014158:Transcription, Genetic / Q000235:genetics; D014779:Virus Replication / Q000235:genetics*
chemical_list: D006511:Hepatitis B Antigens; D007370:Interferon Type I; D011122:Polyphosphates; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D011971:Receptors, Immunologic; C452820:RIGI protein, human; D000071457:DEAD Box Protein 58; D053487:DEAD-box RNA Helicases; C005692:triphosphoric acid
keywords: 3-(4,5)-dimethylthiahiazol-2-y1)-2,5-diphenytetrazolium bromide; 3p-siRNA; 5′-Triphosphated siRNA; 5′-triphosphated siRNA; BF-siRNA; CIAP; ELISA; HBV; HBV e antigen; HBV s antigen; HBeAg; HBsAg; HCC; HepG2.2.15 cells; Hepatitis B virus; IFN; IFNα/β; MTT; NC-siRNA; OD; PRR; RIG-I; RNA interference; RNAi; RT-PCR; TLR; bifunctional siRNA; calf intestine alkaline phosphatase; double strand DNA; double strand RNA; dsDNA; dsRNA; enzyme-linked immunosorbent assay; hepatitis B virus; hepatocellular carcinoma; interferon; negative control siRNA; optical density; pathogen-recognition receptor; retinoic acid-inducible gene I; reverse transcription PCR; siRNA; single strand RNA; small interfering RNA; ssRNA; toll-like receptor